Abstract We define the queens (resp., rooks) diameter-separation number to be minimum of pawns for which some placement those on an n × board produces a with graph rooks graph) desired diameter d . determine these numbers small values

A set D of vertices a graph G=(V,E) is irredundant if each non-isolated vertex G[D] has neighbour in V−D that not adjacent to any other D. The upper irredundance number IR(G) the largest cardinality an G; IR(G)-set IR(G). IR-graph G IR(G)-sets as set, and sets D′ are only can be obtained from by exchanging single for D′. An IR-tree tree. We characterize IR-trees diameter 3 showing these graphs ...

Cylindrical structure analysis is important in several areas and can be performed through the evaluation of diameter changes these structures. Two mentioned: pipelines for oil or gas distribution condition growth trees. In tree changes, monitoring directly related to irrigation, since it depends on water soil deficit trees are global circulation heat water. This change order 5 mm some species. ...